I try the custom control in the sample code for the book Professional C# 2nd edition. No matter where do you put the custom control on the webform, when you start the webform, the control always appear on the up-left corner.

My question is, how do you pass the location in the visual studio designer to the custom control at the run-time?

Thank you very much for help.

Junshi

This sounds like a problem with the forms layout. If it's using grid layout then the positions need to be exact. Also, if your custom control is writing out explicit positioning information in it's rendered HTML then that could be causing the problem. Post the browsers page source HTML if you still can't find the problem.

-Peter

Hi Peter,

Here is a web custom control. Please the control anywhre on a webform. When you run the page, the control is always on the up-left corner.

Thank you for your help.

Jerry

using System;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.ComponentModel;
using System.Drawing;

namespace PCSCustomWebControls
{
    public class RainbowLabel : System.Web.UI.WebControls.Label
    {
        private Color[] colors = new Color[] {Color.Red, Color.Orange,
                                                 Color.Yellow, Color.GreenYellow,
                                                 Color.Blue, Color.Indigo,
                                                 Color.Violet};

        private int offset
        {
            get
            {
                object rawOffset = ViewState["_offset"];
                if (rawOffset != null)
                {
                    return (int)rawOffset;
                }
                else
                {
                    ViewState["_offset"] = 0;
                    return 0;
                }
            }
            set
            {
                ViewState["_offset"] = value;
            }
        }


        protected override void Render(HtmlTextWriter output)
        {
            string text = Text;

            for (int pos=0; pos < text.Length; pos++)
            {
                int rgb = colors[(pos + offset) % colors.Length].ToArgb() & 0xFFFFFF;
                output.Write(""
                    + text[pos] + "");
            }
        }

        public void Cycle()
        {
            offset = ++offset;
        }
    }

What about the form this lives on? If that is set to grid layout that could be what's causing the problem. Otherwise, I don't know. You aren't writing out any other HTML that should result in explicit positioning.

-Peter